Longitudinal changes in brain oxygen extraction fraction (OEF) in older adults: Relationship to markers of vascular and Alzheimer's pathology
Zixuan Lin, Chantelle Lim, Dengrong Jiang, Anja Soldan, Corinne Pettigrew, Kumiko Oishi, Yuxin Zhu, Abhay Moghekar, Peiying Liu, Marilyn Albert, Hanzhang Lu
Abstract
INTRODUCTION: Oxygen extraction fraction (OEF) reflects the balance between oxygen delivery and consumption. We longitudinally measured OEF in older adults to examine the relationship with markers of Alzheimer's disease (AD) and vascular pathology. METHODS: -relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI). The association between OEF and vascular risks, white matter hyperintensities (WMH), cerebrospinal fluid (CSF) measures of amyloid beta (Aβ), total tau (t-tau), and phosphorylated tau 181 (p-tau181) was examined. RESULTS: OEF increased from baseline to follow-up. The increase in OEF was more prominent in individuals with high vascular risks compared to those with low vascular risks, and was associated with progression of vascular risks and the growth in WMH volume. OEF change was not related to CSF markers of AD pathology or their progression. DISCUSSION: Longitudinal OEF change in older adults is primarily related to vascular pathology.